1. Field of the Invention
The present general inventive concept relates to a fixing unit controlling apparatus and an image forming apparatus including the same.
2. Description of the Related Art
When an apparatus receiving a voltage from a switching mode power supply (SMPS) operates abnormally, for example, when a surge voltage is generated in the apparatus, internal elements included in the apparatus might be damaged. In other words, a product liability (PL) accident might happen due to the large increases in current and voltage. In particular, a PL accident might frequently occur in a fixing unit controlling apparatus that controls a fixing unit which includes a heater. In order to prevent a PL accident, a relay that is switched on/off when an apparatus operates abnormally is used to prevent internal elements of the apparatus from being damaged. In this case, however, harmonics noise is generated due to chattering when the relay is switched on/off. The apparatus cannot operate normally due to the harmonics noise.